Dynamic device therapy control for treating post myocardial infarction patients

Abstract

A cardiac rhythm management system includes an implantable device executing a dynamic pacing algorithm after an myocardial infarction (MI) event. The dynamic pacing algorithm dynamically adjusts one or more pacing parameters based on a person's gross physical activity level. Examples of the one or more pacing parameters include atrioventricular pacing delays and pacing channels/sites. The dynamic pacing algorithm provides for improved hemodynamic performance when a person's metabolic need is high, and post MI remodeling control when the person's metabolic need is low.

1. An implantable pacemaker, comprising:
 a pacing circuit to deliver pacing pulses; 
 an activity sensor to sense an activity level; and 
 a pacing controller coupled to the pacing circuit and the activity sensor, the pacing controller including:
 a myocardial infarction detector adapted to detect a signal indicative of a myocardial infarction event; and 
 a dynamic pacing parameter controller configured to be activated in response to the detection of the signal indicative of the myocardial infarction event and to select one set of one or more predetermined pacing parameter values from sets of one or more predetermined pacing parameter values using an outcome of comparing the sensed activity level to one or more predetermined activity level thresholds after being activated. 
 
 
     
     
       2. The implantable pacemaker of  claim 1 , wherein the signal indicative of the myocardial infarction event comprises an external activation command issued in response to the myocardial infarction event, the myocardial infarction detector is adapted to receive the external activation command from an external system communicatively coupled to the implantable pacemaker, and the dynamic pacing parameter controller is adapted to be activated in response to the detection of the external activation command. 
     
     
       3. An implantable pacemaker, comprising:
 a pacing circuit to deliver pacing pulses; 
 an activity sensor to sense an activity level; and 
 a pacing controller coupled to the pacing circuit and the activity sensor, the pacing controller including:
 a myocardial infarction detector adapted to detect ischemia; and 
 a dynamic pacing parameter controller configured adapted to be activated in response to the detection of the ischemia and to select one set of one or more predetermined pacing parameter values from sets of one or more predetermined pacing parameter values using the sensed activity level after being activated. 
 
 
     
     
       4. The implantable pacemaker of  claim 3 , wherein the myocardial infarction detector is adapted to detect ischemia from an electrogram. 
     
     
       5. The implantable pacemaker of  claim 3 , wherein the myocardial infarction detector is adapted to detect ischemia from an electrical impedance signal. 
     
     
       6. The implantable pacemaker of  claim 3 , wherein the myocardial infarction detector is adapted to detect ischemia from an acceleration signal. 
     
     
       7. The implantable pacemaker of  claim 3 , wherein the dynamic pacing parameter controller is adapted to compare the sensed activity level to one or more activity level thresholds to produce two or more activity level ranges each corresponding to one set of the sets of one or more pacing parameter values. 
     
     
       8. The implantable pacemaker of  claim 1 , comprising a pacing algorithm selector adapted to generate an activation signal in response to the detection of the signal indicative of the myocardial infarction event, and wherein the dynamic pacing parameter controller is adapted to be activated by the activation signal. 
     
     
       9. The implantable pacemaker of  claim 8 , wherein the pacing algorithm selector is adapted to time a predetermined time period and generate the activation signal after the predetermined time period expires, the predetermined time period starting with the detection of the signal indicative of the myocardial infarction event. 
     
     
       10. The implantable pacemaker of  claim 8 , further comprising a hemodynamic performance sensor to sense a signal indicative of hemodynamic performance, and wherein the pacing algorithm selector is adapted to determine whether to generate the activation signal using the signal indicative of hemodynamic performance. 
     
     
       11. A method for operating an implantable pacemaker, the method comprising:
 detecting a signal indicative of a myocardial infarction event; 
 executing a dynamic pacing algorithm in response to the detection of the signal indicative of the myocardial infarction event, the executing including:
 sensing an activity level; 
 comparing the activity level to a predetermined threshold; 
 selecting a first set of predetermined pacing parameter values if the activity level exceeds the predetermined threshold; and 
 selecting a second set of predetermined pacing parameter values if the activity level does not exceed the predetermined threshold. 
 
 
     
     
       12. The method of  claim 11 , wherein the signal indicative of the myocardial infarction event comprises an external activation command issued in response to the myocardial infarction event, and detecting the signal indicative of the myocardial infarction event comprises receiving the external activation command from an external system communicatively coupled to the implantable pacemaker. 
     
     
       13. The method of  claim 11 , wherein detecting the signal indicative of the myocardial infarction event comprises detecting an ischemia. 
     
     
       14. The method of  claim 13 , wherein detecting the ischemia comprises detecting the ischemia from one or more of an electrogram, an impedance signal, and a cardiac wall motion signal. 
     
     
       15. The method of  claim 11 , wherein selecting the first set of pacing parameter values comprises selecting a set of pacing parameter values providing for improvement of hemodynamic performance. 
     
     
       16. The method of  claim 15 , wherein selecting the second set of pacing parameter values comprises selecting a set of pacing parameter values providing for reduction of a degree of post myocardial infarction remodeling. 
     
     
       17. The method of  claim 11 , comprising timing a predetermined time period starting with the detection of the signal indicative of the myocardial infarction event, and wherein executing the dynamic pacing algorithm comprises executing the dynamic pacing algorithm after the predetermined time period expires. 
     
     
       18. The method of  claim 11 , comprising sensing the activity level and comparing the activity level to the predetermined threshold continuously. 
     
     
       19. The method of  claim 11 , comprising sensing the activity level and comparing the activity level to the predetermined threshold according to a predetermined schedule. 
     
     
       20. The method of  claim 19 , comprising sensing the activity level and comparing the activity level to the predetermined threshold on a periodic basis.